Maybe it is now simpler than what you can read on such link. dnf install gnome-tweaks
In the Fonts section there is a Scaling Factor option.
In addition, in such link it is stated that GNOME only allows integer scaling numbers to be set. 1 = 100%, 2 = 200%, etc.: it was true until some previous version. Now you can set also floating numbers.
I’m quite sure that it’s for HiDPI scaling, not for font scaling option. I.e. it’s for this setting:
gsettings set org.gnome.desktop.interface scaling-factor 2
And Fonts – Scaling Factor should correspond to:
gsettings set org.gnome.desktop.interface text-scaling-factor 1.5
I’ve been using Font Scaling Factor set to 1,25 for ages (and leaving font sizes to defaults). Also if you enable Large text option in Gnome settings - Accessibility – it actually sets the Font Scaling Factor exactly to 1,25
From my experience, Font Scaling Factor setting forces quite a few (if not all) buttons to become larger when text labels are no more able to be painted inside a button, so to say. On 1,25 buttons’ increase in size isn’t very big. Also for some application it leads to misalignment of buttons, text labels, etc – but again, mainly on larger than 1,25 factors.
Fractional HiDPI scaling – when it works good – should scale all the interface elements proportionally, as far as I understand, and would be a better / more pretty option.